1. Field of the Invention
The present invention is directed towards the field of image distribution, and more particularly towards conducting image collaboration among computers that display the image at potentially different resolutions.
2. Art Background
It has become more common in the medical field for images to be stored, distributed, and viewed in digital form using computer technology: Currently, Picture Archival and Communication Systems or PACS have been in widespread use. In a typical PACS application, image data obtained by imaging equipment such as CT scanners or MRI scanners are stored in the form of computer data files. The size of a data file for an image varies depending on the size and resolution of the image. For example, a typical image file for a diagnostic-quality chest X-ray is on the order of 10 megabytes (MB). The image data files are usually formatted in a xe2x80x9cstandardxe2x80x9d or widely accepted format. In the medical field, one widely used image format is known as DICOM. The DICOM image data files are distributed over computer networks to specialized viewing stations capable of converting the image data to high-resolution images on a CRT display.
In general, collaboration involves the collective participation of two or more people regarding a subject. The subject of the collaboration may involve any type of problem or case, or it may involve the presentation of information for purposes of learning. In the past, a collaboration required people to assemble in a common geographical location to conduct the collaboration. However, with advancements in computers and telecommunications, collaboration among remote users may be conducted using some form of image based conferencing. Image collaboration generally refers to the collective participation of two or more people viewing a common image or portions of a common image. Typically, to conduct image collaboration among computers, the computer hosting the collaboration, referred to herein as the host computer, transmits the image to each of the one or more participating client computers.
Image collaboration has application for use in medical imaging or medical informatics. For this application, a physician conducting the image collaboration may use digitized medical images (e.g., mammogram, X-Ray, MRI, CATSCAN, etc.) to discuss a particular medical case with one or more physicians. For example, a primary care physician may seek to collaborate over a medical case with a specialist by pointing out to the specialist participating in the collaboration particular characteristics exhibited in a patient""s X-Ray.
Although computers are ubiquitous in both home and office, the characteristics (e.g., screen resolution, processor speed, etc.) of different computers are typically different. For example, a notebook computer may contain a monitor capable of displaying images at a relatively low resolution, whereas a desktop computer may contain a high-resolution 19 in. monitor. Prior art image collaboration systems typically require all of the participants in the collaboration to have the same computer equipment. Thus, in the medical imaging application, each physician is required to use the same proprietary computer workstation in order to participate in the collaboration. For example, in the medical imaging application, a radiologist may have access to a high-resolution workstation in the radiology department, while a physician, participating in the medical collaboration, may only have access in his office to a personal computer (xe2x80x9cPCxe2x80x9d), with relatively low resolution. A third physician traveling, who wishes to participate in the medical collaboration, may only have access to a notebook computer. As illustrated by this example, all three physicians have three different screen resolutions, although desire to collaborate over the same image. This limitation severely inhibits the widespread use of image collaboration. Therefore, it is desirable to develop a system that permits image collaboration independent of the display resolution of the participants. It is also desirable to develop an image collaboration system for medical applications, which requires distribution of large data files that requires only the use of thin clients.
An image collaboration system conducts resolution independent image collaboration among a host computer and participating client computers. The subject of the image collaboration involves at least one source image. The source image is stored so as to permit construction of at least portions of the source image at different resolutions. In one embodiment, the source image is transformed into a dynamic transfer syntax representation, also referred to herein as pyramidal data structure. In general, the pyramidal data structure comprises a hierarchical representation of the source image, wherein each level of the hierarchical representation is sufficient to reconstruct the source image at a given resolution.
After establishing communications for the image collaboration session, the host computer displays, at a first resolution, a display image based on one or more of the source images. To conduct the resolution independent image collaboration, the host computer generates a resolution independent description of the first display image that describes the first display image relative to the source image. In one embodiment, the resolution independent language describes a center point of the image displayed, as well as the dimensions of the image. The host computer broadcasts the resolution independent description of the first display image to the participating clients. In response, the participating clients generate an image from the resolution independent description of the image at the host computer at a resolution sufficient for display at the participating clients.
The image collaboration system has application for use in a medical informatics system. In one embodiment, the medical informatics system includes a user interface with a patient browser view and a patient canvas view. The patient browser view permits the user to select studies for the collaboration session. The patient canvas view provides the user the flexibility to arrange the studies, including the images and series within the studies, in any manner desired. The image collaboration system then broadcasts, in the resolution independent description, the entire screen display of the host to provide full context of the host computer display to the participating clients.